config.php

<?php

/**
 * Configuration file for database connection in an e-commerce application.
 * This file defines constants for database connection parameters and
 * provides functions to establish connections with and without specifying a database.
 *
 * @author CLÉMENT Timothé
 * @version 1.0
 * @since   12-01-2026
 */

/**
 * Database host address
 * @var string
 */
const DB_HOST = 'localhost';

/**
 * Database username
 * @var string
 */
const DB_USER = 'root';

/**
 * Database password
 * @var string
 */
const DB_PASS = 'password';

/**
 * Database name
 * @var string
 */
const DB_NAME = 'ecommerce_db';

/**
 * Establishes a connection to the MySQL database.
 *
 * Creates a new MySQLi connection using the previously defined constants.
 * If the connection fails, it terminates the script and outputs an error message.
 *
 * @return mysqli The database connection object
 * @throws Exception and terminates the script with die() if connection fails
 */
function getDBConnection()
{
    $conn = new mysqli(DB_HOST, DB_USER, DB_PASS, DB_NAME);

    if ($conn->connect_error)
    {
        die("Connection failed: " . $conn->connect_error);
    }

    $conn->set_charset("utf8mb4");
    return $conn;
}

/**
 * Establishes a connection to the MySQL server without specifying a database.
 *
 * Creates a new MySQL for development purposes where database selection is not required.
 *
 * @return mysqli The database connection object
 * @throws Exception and terminates the script with die() if connection fails
 */
function getDBConnectionNoDB()
{
    $conn = new mysqli(DB_HOST, DB_USER, DB_PASS);

    if ($conn->connect_error)
    {
        die("Connection failed: " . $conn->connect_error);
    }

    $conn->set_charset("utf8mb4");
    return $conn;
}
?>